July 2005 - Report and Summary

The month of July 2005 saw normal temperatures and above normal rainfall. Compared with July 2004, the month was 1.9 deg. warmer, and 2.49 inches wetter. The rainfall deficit for 2005 and the previous year continues, though it was not as severe as was the case at the end of June. Rainfall through the end of July was 7.93 inches less than normal, representing a 31.7 percent precipitation deficit. The percentage deficit at the end of June was 39.2. Year-to-date rainfall was 11.13 inches less through July 31, 2005 than was the case at the same time in 2004. Twelve-month accumulated rainfall was 6.39 inches less through July 31, 2005 than through July 31, 2004. Precipitation during the previous twelve months showed a 23.8 percent deficit, compared with a 29.3 percent deficit at the end of June.

A dry July 2004, and July's low normal rainfall combined with the above-rainfall of July 2005 to account for the changes in these percentages. Nonetheless, East Texas remained in moderate drought at the end of the month, with the dry period having begun in July 2004. The thirty-day outlook for July 2005 had called for near normal temperatures and near normal precipitation.

The week June 26-July 2 saw temperatures about 3 deg. warmer than normal, and rainfall about 80 percent of normal. The high temperatures were the result of dry vegetation and soils, and an upper air high pressure ridge. An upper air disturbance, crossing in the northwest flow aloft late in the week, was responsible for rain on the 1st and 2nd. The week's average temperature was 84.8, and precipitation was 0.55 inch. The week was 3.1 deg. warmer than the previous week. Compared with the same week in 2004, the week was 7.1 deg. warmer, and 2.64 inches drier.

The week July 3-9 saw temperatures about 1 deg. warmer than normal, and rainfall about 20 percent of normal. The upper air high pressure ridge persisted, though it was weaker than on the previous week. Another disturbance crossed on the 8th and 9th, bringing the week's rainfall. The week's average temperature was 84.2 deg., which was 0.6 deg. cooler than the previous week. Rainfall was 0.10 inch. Compared with the same week in 2004, the week was 0.8 deg. warmer, and there was no rain during the week last year.

The week July 10-16 saw near normal temperatures, and rainfall about 200 percent of normal. For most of the week, winds aloft were northwesterly. This permitted a couple of weak surface boundaries and a series of upper air disturbances to drop into the region. The result was mainly afternoon and evening thunderstorms on most days during the week, with a few occurrences of heavy rain. The week's average temperature was 83.4 deg., which was 0.8 deg. cooler than the previous week. Rainfall was 0.97 inch. Compared with the same week in 2004, the week had an identical average temperature, and there was no rain in 2004.

The week July 17-23 saw temperatures about 1 deg. below normal, and rainfall about 350 percent of normal. Upper air high pressure re-asserted its control over the area on the 19th, though heavy rains had fallen at some locations on the two previous days as the northwest flow event came to an end. As a consequence, the period between the 19th and 23rd was mostly dry. A disturbance dropped around the southeastern edge of the upper air high on the 22nd, and caused isolated occurrences of flood- producing rains. The heaviest of these were over "Rusk County, where more than four inches fell. Subsiding air around the north fringe of Hurricane Emily, which came ashore south of Brownsville on the morning of the 20th, contributed to the warm and dry weather. The week's average temperature was 82.9 deg., which was 0.5 deg. cooler than the previous week. Rainfall was 1.54 inches. Compared with the same week in 2004, the week was 0.8 deg. warmer, and 1.52 inches wetter.

The week July 24-30 saw near normal temperatures, and rainfall about 5 percent of normal. Early in the week, upper air high pressure dominated the region, bringing warm and very humid conditions. An unseasonably early cold front crossed on the afternoon of the 27th, lowering temperatures and bringing showers and thunderstorms. The southern counties remained dry, with the heaviest rains occurring over the eastern and western counties on the 27th. The week's average temperature was 83.6 deg., and rainfall was 0.03 inch. The week was 0.7 deg. warmer than the previous week. Compared with the same week in 2004, the week was 4.9 deg. warmer, and 0.18 inch drier.

KEY TO SYMBOLS:

A = HAIL

B = BLOWING

D = DUST

F = FOG

H = HAZE

IP = SLEET

K = SMOKE

L = DRIZZLE

R = RAIN

S = SNOW

T = THUNDERSTORM

Z = GREENWICH MEAN TIME

ZL = FREEZING DRIZZLE

ZR = FREEZING RAIN

- = LIGHT

+ = HEAVY

The reporting period for temperatures and phenomenon on each day is for the twenty-four hours ending at midnight hours GMT--6 p.m. CST and 7 p.m. CDT. The reporting period for precipitation is for the twenty-four hours ending at noon GMT--6 a.m. CST and 7 a.m. CDT. All times are given using the twenty-four hour clock, and are expressed in Greenwich Mean Time.

Observations are from NWS Station 41/9207/4 in Tyler, Texas. The term "normal" refers to averages from the standard climatic period 1971-2000.